Pressure medium operated mechanism



May 20, 1969 s. A. R. HANSEN PRESSURE MEDIUM OPERATED MECHANISM Filed Jan. 17, 1967 FIG. 7

United States Patent 3,444,789 PRESSURE MEDIUM OPERATED MECHANISM Sten Anders Runeson Hansen, Lerum, Sweden, assignor to Associated Cargo Gear AB, Herkulesgatan, Sweden Filed Jan. 17, 1967, Ser. No. 609,920 Claims priority, applicatiorzgweden, Jan. 24, 1966,

Int. Cl. F01c 9/00 US. Cl. 92121 2 Claims ABSTRACT OF THE DISCLOSURE A rotary actuator including at least one radial vane operable in a chamber provided with a stepped rotor shaft journalled in lids forming the ends of the chamber. The lids have hub portions of about the same diameter as the thicker middle portion of the shaft and each vane is longer than such middle portion and extends outward over the hub portions. The edge of each hub portion and the juxtaposed edge of the middle portion of the shaft is recessed to provide a groove of substantially T-shaped cross section. A correspondingly shaped sealing ring is mounted in the groove and the extended parts of each vane sealingly bear against the upper side of the flanges of the T.

The present invention relates to a pressure medium operated mechanism in which a rotor having at least one radial vane is mounted in a cylindrical housing provided with end lids or covers, and having at least one radial wall subdividing the chamber in the housing into compartments adapted to be supplied with a pressure medium, in order to bring about a turning of the rotor in one direction or the other.

The object of the present invention is to provide a simple, reliable and compact mechanism of the type described by arranging the sealing means between the shaft and the end lids in a novel and characteristic manner.

The invention is characterized in that the diameter of the part of the rotor within the housing has a larger diameter than the end parts of the rotor extending through and journalled in the lids, that each lid is provided with a hub portion having essentially the same diameter as the middle part of the rotor and directed towards the interior of the housing and terminating a distance from the middle portion of the rotor, that a recess is formed in each of the juxtaposed surfaces of the middle portion and the hub portion, respectively, and that a sealing member, having an essentially T-shaped cross section is located in the space thus formed, with the radial web portion of the T being inserted between the hub portion and the middle portion, respectively, and the flanges of the T resting in the recesses therein.

The invention will below be described with reference to the accompanying drawing on which FIG. 1 is a side view partly in elevation and partly in section of one embodiment of the invention, and FIG. 2 is an end view partly in elevation and partly in section of the mechanism.

The mechanism consists of a housing comprising a cylindrical part 1 and two end lids or covers 2, with the latter components being attached to the housing by means of bolts 3. The housing encloses a rotor shaft 4 arranged coaxially with the housing. A middle portion 4b of the rotor is designed with a larger diameter than its end portions and carries two radial vanes 5 which are designed to closely fit the internal walls of the chamber surrounding the rotor. The vanes are connected to the rotor by means of bolts 6, and further vanes 7 are fixed to the cylindrical part 1 by means of bolts 8, as shown in FIG. 1. These vanes subdivide the chamber within the housing into a number of compartments 1a, 1b, adapted to be supplied with a pressure medium in an arbitrary manner (not shown). Both types of vanes 5 and 7, respectively are at their edges provided with sealing strips 9 adapted to engage the rotor, the end lids and the internal Wall of the housing, respectively.

As shown in FIG. 1 the end portions of the shaft 4 have a smaller diameter 4a than the middle portion thereof and are carried in the end lids each of which is provided with a hub portion 2a extending into the housing. The hub portion does not extend fully towards the middle portion, but each hub portion is provided with a journal bearing 10. This bearing extends, as shown in FIG. 1 somewhat beyond the end surface of the hub portion 2a thereby locating the shaft in the axial direction. The inward edge of each hub portion 2a and the juxtaposed edge of the middle portion 4b of the shaft 4 are received in such a manner that an annular T-shaped groove will be formed. Within this groove an annular sealing member 11 having a correspondingly shaped cross section is mounted. The flanges of the member 11 are located in the recessed portions between the hub portions and the shaft and the web of the T is inserted between the juxtaposed end surfaces of the middle portion and the hub portion, respectively.

The external surface of the sealing member -11 is cylindrical and has essentially the same diameter as the middle portion of the shaft and hub portion 2a. The middle portion of the shaft, the sealing members 11 and the hub portions 2a of the end lid will thus together form a continuous cylindrical surface. The vanes 5 and 7, have a longer axial extension than the middle portion of the rotor. This makes it possible for the vanes to engage the external surface of the sealing member and retain this member in proper position.

The design of the mechanism may in this manner be simplified which makes the manufacturing cheaper. By the design and location of the sealing means 111, the hearing for the shaft 4 may furthermore be comparatively long. Hence, the load on the bearing and consequently also the wear thereof will be low, without the total length of the mechanism being increased. The pressure medium will force the member into the groove which increases the sealing action.

The axial locking of the shaft, which in the illustrated embodiment is obtained by the engagement of the journal bearings 10 with end surface 4a may instead be obtained by separate distance pieces cooperating with, and possibly recessed into the end surfaces of the hub portions. In this design the internal flange of the sealing member 11 will extend to the shaft and furthermore the cross section of the sealing member 11 may vary. The plain journal bearing 10 may be substituted by a ball or roller hearing.

I claim:

11. In a pressure medium operated mechanism having a rotor provided with at least one moving radial vane mounted in a chamber defined in a housing provided with end lids and at least one fixed radial wall subdividing the chamber into compartments and means to supply said compartments alternatively with a pressure medium in order to bring about a turning of the rotor in one direction or the other, a middle portion of the rotor hav ing a larger diameter than the end portions thereof, a hub portion of each lid directed towards the chamber, said hub portions terminating short of the middle portion of the rotor and having essentially the same external diameter as said middle portion and adapted to carry the end portions of the rotor, each of the juxtaposed surfaces of the middle portion and each hub portion having a recess, an annular sealing ring of essentially T-shaped cross-section located between each hub portion and the middle of the rotor, the radial Web portion of the T-shaped ring being inserted between the hub portion and said middle portion and the flanges of the T-shaped ring resting in said recesses, and the vanes being longer than the middle portion of the rotor and extending outwards over the hub portion bearing against the flanges of the T-shaped sealing ring.

2. The pressure medium operated mechanism according to claim 1 in which each hub portion is provided with a journal bearing extending beyond its inner end and engages the end surfaces of the middle portion of the rotor to locate the same axially with respect to the housengaging the extending part of the journal bearing.

MARTIN P.

References Cited UNITED STATES PATENTS Smalley 277225 Hemphill 92125 Sneen 92-122 Traugott 308187.1 Herbst 30836.1 Rumsey et al. 92125 French 92-12 1 SCHWA DRON, Primary Examiner.

I. C. COHEN, Assistant Examiner.

US. Cl. X.R. 

